Speaking for myself it's just the variety and the flavors at your disposal. Im preparing for a full retirement in a few weeks so I was only in this for a few months. I'm not into caucasian women in my personal life and I've only seen three caucasian women doing within this, all three were independent before I started this hobby. In my personal life I've dated (no intimacy)very briefly only two caucasian women and that was a lifetime ago. So only in this area I would would actually see a caucasian woman, never in a relationship or a one nighter. Last month I had an itch to see a PAWG but never went forward with it.
Last encounter outside of this (personal life) was a one nighter and a half in Aruba with two locals. One was an actual one nighter while the other was a CBJ. Not much effort when your away on a vacation outside NYC. in reality I rather enjoy my drink and the music rather than look to hook up with women.
I have zero issues going on dates or getting women. Most men are just not good at attracting women or even getting a simple date. So most of them resort to this hobby to fill that void but in reality it's doing more harm than good when they STILL lack physical appearance and good *personality* to attract women. This is why you have sexually frustrated guys (incels) shooting up the place. I saw a Vice video and all of those guys are just boring as fuck, have no interest (hobbies) and are negative. I'm a man and I wouldn't be near any incel if you paid me too.
I bumped into two mongers recently both were overweight and I can imagine they types of dudes these women see consistently. All the independent providers I've seen outside this hobby told me the ratio of unattractive men they see is way high than the attractive ones.
TL
R : i do this for the variety of women I wouldn't want to fuck or do want to fuck in my personal life. Guys also do it for the same but a large majority do it because they can't get laid or get a simple date, so this filled up that void.