Where there used to be about a dozen different shirt styles in 4-5 colours, there are now more things than anyone will ever buy.
While of course there is standard fare... like the aforementioned shirts - now in more styles, roughly the same number of colours, but with four different images that configure in a metric tonne of different ways - like hoodies and pyjamas
There is also fairly common stuff like coffee cups, water bottles clocks, baby-onesies, hats and iPhone cases....
(Note that the images here are merely the smallest sample.)
As well as utterly stupid stuff like Dog T-shirts, coasters and throw pillows... that is if you really need a Beast of Bottomless Lake Dog T-Shirt..