With many different types of thistle there is plenty of opportunity to photograph colorful wild flowers, like this one which I believe may be Canada thistle.
The bright flowers are a draw for many different types of insects, like this tiger swallowtail on a bull thistle flower.
And if I really have to take pictures of birds at feeders well then this is the type of feeder that I prefer to look for. During the summer and fall wherever you find thistle chances are that there will be some goldfinch around. It is really fun to watch them pick apart the thistle looking for the seeds inside.