Scott, the BIM server manager or the server/project administrator can do 'force leave' for that user so the elements reserved by that user get released.
The other thing is, many times the reservation of elements becomes very selective, so that time releasing all and then reserving again on next login could be tedious or time consuming. So the release all' option should come as reminder and also as an option (not mandatory) while logging out.
That will be better i think.
Dhaval Shah
Upto AC 22
iMacs and MacBookPros: Mac OS X (10.6 to 10.12, Intel core 2 Quad to i5, i7, 8 GB to 16GB)
Win 10, AMD Opteron 6-Core x 2, 16GB, FirePro W4100 2GB
& ThinkPad E550
& i7, 8GB