Well, again it depends
What I did should not be seen always as the norm in the business.
Simply, for a very personal reason I will be OK from next month with overnights, thus I can encourage them by providing a lower fee in certain situations. But if I wouldn't be that eager to do them, I will probably like the same reular higher fees in both situation (active night or not so active night), because if forget about my personal time off and privacy when I was used to get it, at least I may do it for something that is seen as appropriate compensation.
There is no right or wrong in this, really, it all depends how the escorts feel about overnighters and what clients wish to achieve from those. As long as both have an idea what they will get into, it is perfect.