fuel shenanigans

I'm not one for conspiracy theories, but the gas stations could be up to something...

never have i ever, had a fill up of more than 14.7 gallons. Even when running on fumes and a prayer the maximum fill up has been 14.7.

But lately, I've had to fill up to 14.8 and 14.9. Last night, my tank required 15.1 gallons.

I wonder what the explanation for this is. Could it be that my gas tank has spontaneously grown?