Why would you put in the IRA or 529 when you do not intend to use the 2% rebate as contribution to those plans?

Yes, if you put the rebates in those plans, those are considered part of your annual contribution and you would NOT be able to take it out without tax penalty. There is no "tricks".

Please remember the IRA and 529 are NOT Tax Exempt, it is Tax Deferred.

The 2% earning from this card is NOT taxable.

The rebate is NOT taxable, so what is the purpose to put it in the IRA or 529?

By putting it into the IRA or 529 plan, you essentially turn a NON-Taxable money to a Tax-Deferred money that ultimately you would be taxed upon withdrawal.

This is as dumb an idea as holding municipal bonds or treasury in an IRA account because there is no benefit in deferring tax on interests when there is no tax to begin with.

So what is the benefit for doing so, and then try to find a non-existent "trick" to get the money out?

Fido is a brokerage in a regulated business. There is no way you would get away from not paying "tax penalty" by taking money out of qualified plan before you are qualified. period.

Why dont you just use the regular brokerage account? It is free by the way and has some benefits such as the 0 forex fee ATM card, and a toll-free number in many countries.