Clarence: Yes, they were pretty tacky, way back when.
The Geek: Personalized t-shirts seemed to be worn mostly by schmaltzy couples, doting dads or niche advertising, like a local church group or small business - and they were usually made by a local small business.
With exponential improvements in Printing technology, a new industry is emerging, in which an artist + a website + Social Media (via fans or PAID ads) can access STATE OF THE ART technology, Packaging & Distribution through third party services.
In fact, the distributor that I presently use has 3 fulfillment centers (Printing, Warehouse, Distribution etc.) one each on both coasts of the USA + another in Europe - altogether, a reach of an enormous, 650 million customers, a HUGE percentage of the present ONLINE SHOPPING world.
NOTE 1: The company that I use, presently offers t-shirts, socks, caps, leggings, skirts, posters, framed posters, tote bags, mugs, pillows & iPhone cases.
NOTE 2: The LOCATION of the fulfillment center is EXTREMELY from the customer's point of view, because, besides SHIPPING COSTS, if the fulfillment center is not in the customer's HOME COUNTRY, their government will probably impose IMPORT DUTIES.
Thus, Suburban Geek, though Australian-based, may not presently be a viable option for Australian customers, because SHIPPING + IMPORT DUTIES really adds up! However, the gossip is that the fulfillment center's NEXT expansion is planned for Australia - so, fingers crossed!