This myth will not die...
A company that collects your donations cannot claim those donations as tax deductible. They are your donations; you can claim them on your taxes.
Even if the company could claim them, it would be income that they would then offset, resulting in a net of zero. There would be no benefit to this.
Companies cannot and do not claim your donations to receive tax benefits. Companies do a lot of shitty things, but soliciting pocket change en masse for charities is actually one of the few good things they do.