A Bengali is already President of India, Pranab Mukherjee.
As I have said earlier, people of West Bengal don't hate or look down upon the Bangladeshis. Some of them have close relations too.
There is little reason to hate. However, there are some Bangladeshis, and many of them are not Bangladeshis any more, for they have migrated to UK or elsewhere, they have a thing or two against India. These are the same people who were against creation of Bangladesh from East Pakistan. Some are their next generation. Some of them support the creation Bangladesh to appease the majority and yet hate India nonetheless.
I have seen some of them commenting here, which are less logical and more rants. A typical knee-jerk reaction follows and before you know, you have a war of words at hand. There are typical red-neck types in India too. But I think if nobody incites them, they will mind their own business. Most of them have little to do with West-Bengal and Bangladesh anyway.