Why did Bill and Tom Kaulitz become vegetarians?

well so far im trying to found out the real reason to

but to my knowledge it is because they are fighting against animal abuse, i guess they find it wrong to eat meat because the animals are treated harshly

but, recalled from the past, Bill said that he would NEVER or COULd never be a vegetarian because he does not like most vegetables so much and he loves to eat Big Macs. so Bill from the past and Bill in the present are clashing into he own ideas and believe

but what can we do we are all human~!