Sounds rather extreme to me because your tone is verging on hating on all things animal related.
Yes, you've got me there, I don't eat meat because secretly I hate animals.
Seriously, are you trolling or just dense?
I think you have just confused yourself there. Murderer kills and a theft steals. There is a huge different there. Former terminate life while the latter not in the context of the bike but both are wrong in their actions.
Both are wrong in their actions. Ok. So. Why is it not ok for you to buy a stolen bike (which is wrong, as you say) but is ok to eat an animal that's been killed? In both cases, you've not asked for the crime to be committed, in both cases the supply is there whether you buy the bike / meat or not. This is your argument in its entirity. Look.
Consider these questions as they are about your intention.
1) Did you demand the bike to be stolen for your use?
2) Did the thief intentionally steal the bike for your use? i.e. they know you like expensive bikes so stole the bike awaiting your patronage.
3) Did you request the bike to be stolen for other to buy?
4) Did you tip off the thief or someone who you know would steal or buy it?
5) Did you steal the bike yourself for sale?
... so, if you can answer 'no' to all five of these, why is it wrong to buy a stolen bike?
If I understand your explanation correctly you filtered out/denied all or some of the external influences which in effect failed to take into account all possibilities. What you are doing is actually rather irrational since you have denied/ignored some of the information.
... such as? Give me an example.
Although you have classified yourself as a veggie I am sure you have done some proxy killing of animals
I class myself as vegetarian because I don't eat meat. It's really quite a simple concept. It's only for ease of explaining to others that I feel any need for classifications and labels at all.
As for proxy killings, I'm assuming you mean like wearing leather, in which case yes. But then, I never claimed otherwise. Seems you're still labouring under the idea that I'm operating under some broken moral code which says I can't eat rabbits because they're cute or something.
Incidentally, go look up "extreme" in the dictionary. You keep using that word, I do not think it means what you think it means. Compare these two vegetarians:
1) "sure, eat meat, it's your decision what you eat"
2) "meat? How dare you! Meat is murder, OMG, I can't believe you're going to eat steak, don't you know what they do to cows?"
You have just demonstrated the irrationality in such issue. 
