Second hand games may be the cause, but not for the reasons given.
Take a look at the car market. The second hand market supports the huge retail price of brand new cars. If people didn't know that in a few years time they would be able to sell their new car as second hand and recoup some of the money the majority wouldn't be willing to pay such a high price in the first place.
Very few people would be happy to shell out £50 for the amount of games they currently buy if they didn't know they'd be able to trade it in later. Without the second hand market the current price structure couldn't be supported.
If the moves to ban second hand game sales succeed then there are several possible outcomes:
1) The industry is badly hit as gamers cut the amount of games they buy because they can't afford to pay for so many games with no way of getting any of the money back.
2) Piracy soars because former second-hand gamers aren't willing to pay £50 a time.
3) The industry drastically cuts the new price. This would likely result in fewer games being made because of the high development costs.
If the industry succeeds in getting second hand games banned they deserve everything they'll get.
