In regards to biscuits and non sexual services. This has very much been my experience in Hong Kong/Japan (but not South Korea).
The small walkup sub divided flats to get around the brothel laws. Granted it is a tiny space but it is a more complete service in terms of doing little things for customers.
For instance when you go in they will generally undress you and hang your clothes up or put them in a maniquin or hangers at the very least.
The WG will often provide a small fridge of chilled drinks, alcohol free beers, soy milk, lemon tea, etc and often a small basket of single serving snacks things like after8 mints or Ashi jellies. Jelly cups are popular, I always like the Chocomints WG all seem to have (its like a minstral but with a XXXX mint inside.
They will also give you a nice soap up and wash down in the shower before and after the event. (this does not burn into the time BTW).
They'll dry you off and adjust the lighting and the temperature and ask if you're comfortable switching pillows in and out.
Then the service (and the clock) starts.
Many are masseuses and will give ok massages too before or after the event. (this does burn into the time).
Afterwards they'll join you in the shower. Dress you so you're presentable and then you pay (all the above is hunting for tips) and leave.
The big saunas make a bigger song and dance about it. Where you can use their steam rooms for a bit get a vanilla massage (usually from a guy) and generally get given 2 tokens for drinks (one alcoholic the other soft). Again they do this to hunt for tips as the brothel manager will usually bow at you with his tip box in his hands. You can even order food delivery and watch their satellite TV for a bit.
While the UK scene the sex seems to be the major aspect of it.
Go in, pay, get undressed (self) hop on bed, bang away shoot.
Check clock
Maybe chat.
Bang again shoot.
Shower... leave..