Just had a quick look through Friday night games this season (up to round 13) and last.
Home teams:
Bristol, Gloucester, Sale 7
Newcastle 5 (in just 1 season)
Bath, Northampton 4
Quins 3
Worcester 2
Wasps, Leicester 1
Irish, Sarries, Exeter 0
Not sure we can have too many complaints. In fairness to PRL/BT, I think they try and keep the Friday night games to those teams who have indicated that they are happy to play on Fridays wherever possible (Sale, Bris, Glaws, Newcastle). They've got schedules to fill though, made all the more difficult when they are having to fit around the 6N.