Of course, most BP boycotters would be pained to realize that it also would likely hurt the Gulf clean-up itself.
As I pointed out in the comments, if a firm’s share price drops, it has greater difficulty raising capital. If it has greater difficulty raising capital, it is less able to fund expensive projects, like the gulf clean-up.
And yes they had billions in profit last year, but that is no panacea. Besides whatever damages BP will have to pay, they also have to clean up a portion of the earth that is visible from space. Somehow I doubt financially crippling BP would help that endeavor.