There is no way level 10s are getting 60IP per wall hit, not even close. Not to mention you have to take the wall down first. I reckon it's closer to 20IP per hit hit before and 40IP per wall hit after wall goes down (or even less than 20/40). Further, fairly certain you always get more IP from taking down a player than a wall hit, but I'm not in the business of hitting level 10s, so I can't be sure.