We usually don't have that problem as we come in on a Sunday and leave on Thursday avoiding the weekend crowd. When there is no one behind me, I take my time. But if there is even one person waiting,I try to get it done as fast as possible.Then pull forward and finish up washing my hands etc.But some people don't care about others.I have observed the same behavior at the fuel pumps.I remember pulling into a Flying J in Wyoming. There were 2 units at the RV lanes but no one was around. I waited 20 minutes and still no one came out so I then pulled over to one of the regular pumps and was able to fill up there. We do have a sewer clean out next to our trailer at home and use that if we camp local. But when you're on the road you don't have that option.