You won't get a bar girl for 74 baht! That amount is just over $2 US! A hooker fee would not show up on a hotel bill anyway! Some "green" tourists might pay a lot for a lady but local expats (the ones without girlfriends or Thai wives) would probably pay something closer to 500 baht to 1000 for the lady and if she is at a bar a fee to sign her out.
The Grace Hotel is popular with Middle Eastern tourists. That area has many restaurants that cater to Middle Eastern tastes.
Edit [Moderator]: Link removed
Some hotels will charge a fee for a tourist to bring a guest back to the hotel but that would not show up on a hotel bill either and it would not be an odd amount. This also applies to the many female tourists who purchase "dates" in Thailand.
There is no trick or way a hooker or bar girl can fool a man into taking her to a hotel! They don't use any drugs, they don't force them with knives or guns - if a guy goes to a hotel with a woman it is because he wants to! Some tourists are so stupid they think they have a girl but it turns out to be a katoey (guy that looks like a girl, even with big boobs, maybe surgically altered-maybe not.) If he had a date with a "lady-boy" his chance of getting infected may be even greater! Katoeys are popular with some Middle Eastern men, some kind of exception with the Koran or something???
Maybe easy availability might influence him to do something he would not do at home but it is a choice the guy (or Farang woman) freely makes! No tricks - no gimmicks!
Too bad - so sad!