Side-stepped disagreement -- I'd have to hire 2 additional engineers just to handle the number of unsolicited (a.k.a. "bulk" e-mails sent to a dozen different places with "Dear Sir" at the head) sample requests that come in here. Many would find sites that have "Free Sample!!!" all over them as a reason to be cautious.
And without a doubt, some of the least qualified places I know offer free samples. One or two of them (that I know of) actually solicit samples from other mastering facilities for various 'marketing' (for lack of a better term) reasons. Point being, offering - or not offering samples doesn't necessarily indicate professionalism or qualification.
That said -- YES INDEEEEED, there are some very ropey (assuming "ropey" means "less than obviously qualified") operators out there... They're friggin' everywhere. Just had my gear list pulled from one of them (again...) a few days ago.
Well, not my entire gear list -- Everything except the monitors (they had their KRK Rockit G2's on the page). But I digress...
Of course, I'm not suggesting not using common sense -- If there are no verifiable credits, if there is no engineer named, if the gear list and the photos don't have anything in common, if there's a $75,000 gear selection and a $99 price tag - Sure - those are definitely reasons to be suspicious.
Back to the point - there are plenty of qualified facilities out there that don't offer samples -- Due diligence is the responsibility of the client also -- I don't mix often anymore, but when I do, I decide on who will be doing the mastering based on what I'm looking for - I'm not sending out sample requests to a collection of various engineers to see which one can happen to pull it through the garden the best in one shot -- I'm looking into past experience, credits, a gear selection I'm comfortable with, etc. Just as anyone who is serious about their own work should do.
I remember when this "sample craze" first started whipping up -- It was just several years ago. I'm still waiting for restaurants to offer free samples of different steaks when you walk in so you can decide which steak you want -- Or if you even want to dine there. Or gas stations could start offering a free gallon of gas before you fill up to see if your car runs better (and of course, there would be a certain population that would go from station to station collecting free gallons). One colleague describes it as "Going downtown and asking h**kers for free bl*wjobs" before you decide which one to spend an hour with" --
Personally, I think it does more harm than good to the industry as a whole and I'm looking forward to the day it fades away. That and the end of the volume war.
And let me explain that - as it seems somewhat contrary to my hardcore red-white-and-blue-blooded fair-market capitalist leanings ---
The "free sample" thing is what actually allows the "ropey" types to compete where otherwise, they wouldn't have that avenue available. So instead of a "normal" economic matrix running the show, you have a certain population (let's call them "rookie engineers" and not in a condescending way) that are looking for mastering services -- and a whole bunch of "rookie mastering engineers" - hardly more qualified than the original rookies, trying to supply those services.
As 90% of the time, they're really only serving each other (as the "RM's" can impress the "RE's" simply by slapping a Sonic Maximizer into a cracked L2 and they think they're getting a quality product), they're expanding the "low end" of the spectrum - The median quality bar is going down while the overall industry gets watered down. And that eventually leads to (and it's already happened) the biggest places with the most qualified engineers to downsize, go out of business, drastically cut back on their rates to compete, etc.
And the competition part isn't the problem -- Much of it stems from nasty amounts of software piracy ($8,000 plugin collections - $200 monitoring chains), which impresses the less experienced clientele (again, lowering the bar) and it all slides downhill from there. There's a difference between "fair competition" and "lawless scumbags who should be thrown in jail for theft" -- there are far too many of those.
And of course -- They're the ones that started the "free samples" call years ago.