Now THAT is an interesting concept rather than blocking other adds content you instead have add blocks. Real life adds are dull or childlike since the only people seeing them are going to be kids too young for AR, adults without it and unlikely to afford your products or mages. Meanwhile the real money is in renting space and letting the company buy the uncontested rights. So an add block (storefront, building facing, bus sign, etc) has a series of tags and when the right AR filter views it you get whatever it is has paid for that space. You could even run different content for different filters e.g. ar with corp id, ar without corp id, seasonal varients of the same building front, content linked to whatever movies are currently showing, special content for adults in certain light districts and so on.
For example a plain white tshirt with "Insert add here" tagging. Are's clients see Are's adds in their AR, Shiawase see shiawase adds, non-ar people see a white shirt, general populous (national sin) see whatever add paid the most for the "open slot"on the shirt, certain highly skilled programmers use it to pass mostly hidden messages to each other about their leet skills and technomancers get a splitting headache because they see it all at the same time. Could even be a source of amusement for hackers with programs to cycle through the different filters and see whatever takes their fancy at the time.