Exactly right. I know of countless ML's and WL's that have boyfriends and still hang out with punters outside the shop. One regular WL I know of has had 2 ex-boyfriends and a current boyfriend and all were/are customers. If she is willing to break up with one, what's to say she won't do the same thing to you ? Its 100% guaranteed.
At the end of the day, the relationship is purely transactional be it the WL is getting money, a roof over her head or other things, it won't last. I made the promise to myself to never get involved with a WL/ML again and that's been 4 years. Sure, be kind to them and chat with them on and off but keep it at that. Heading out for a coffee or going to the club is fine but again, keep it at that.
One popular WL from a shop was offering BB to customers without his knowledge despite her promising him she doesn't do it. I thought fucking hell, thank god we are not dating and that we were using a rubber the entire time.
Just my thoughts.