Canadian High Interest Savings Bank Accounts

My girlfriend wanted to open a HSBC account to get the interests promotion rate of 1% extra for the first month. She asked me if I wanted my name on the account so we could have our common account for the future when we'll have to pay our transactions we both make on our credit card.

However, since I already had an account with HSBC they do not let her have the 1% promotional rate even is she's the main owner of the account.

Now I understand why bank are rich, they have some loosy politics they fit to their needs when it arranges them.