When I first started punting I used to feel guilty an odd time, I guess it is a catholic upbringing. One WG that I see regularly told me there is no need to feel any guilt and just enjoy the experience. I have never looked back since then. You are paying good money to empty your load into/on to a good looking woman, why should you feel guilt? The more you punt it will get easier.
I am almost 40 and more than 1 pop is out of the question for me, so I just book 30 mins, or 45 if the WG is exceptional. Any longer is just wasting money that could go on another punt.