Actually it doesn't seem to work this way. There is a reason why most seem to pick Waltham/Burlington/Woburn or Dedham/Braintree instead of Boston.
Much fewer people live in Boston than in the burbs. Most of visiting businessmen/professionals don't stay in Boston but come to companies along 128 belt. Boston has a lot alternatives to offer, but if you're stuck in a hotel along 128 there isn't much for you to walk to. So you go and see an escort. + Boston parking issues + Boston traffic - you get the picture. Unless you're Kimmy it would always be slow for you in Boston.
As for Waltham being at the sights of LE. Sure. But so is Boston, and LE is much more active in Boston. I'm sure that all receptions in Waltham hotels know who and how and what and where and why. The same as in Boston hotels, or hotels the world over. People that work there are no idiots. It's just if there is no reason to ask, there is no reason to tell.
So if there is no commotion and no complaints the hotels would rather just let the sleeping dog sleep and not become known as 'prostitution hang-outs' and placees with increased police presence. Especially along 128 belt where crime is nowhere near Boston level and nobody wants cops around unless they really feel they need them around, like might be in Boston.
These are private businesses after all. They don't have to report what they might or might not suspect unless it's something truly outrageous. Whatever makes money works. Negative advertisement in mass media could only hurt their bottom line.
That's why the hotels are safer than apartments. Hotels are dynamic with ever-changing clientele. With apartments you're dealing with situation which is stationary and eventually neighbors get bothered and call cops. Point in question - BTT and the latest Chinese agency bust in Allston.
The reason Asian agencies rent apartments is because it's more economical fixed-costs wise and they really don't care about what happens to those that run them, their girls, or their clientele. The big boss is always in the home country. Those who run it are girls' managers and bosses in name only. As BTT bust showed LE would always spare the girls (victims), and just go after the "owners" (pimps, exploiters) and us (the pervs), because I'm sure I won't discover the bicycle here for anybody but in the modern United States if you're a man you have little to no rights. Thank God they at least allow us to hire defense councils, eh? lol