I see what you mean Kay... so with that thought only the cheapest agency will survive in the jungle. Anyway your feedback is very interesting. I take note.
I'm no expert on Microstock and don't want to be, so please someone correct me if I am wrong here. My understanding of Microstock agencies is that the client pay a subscription that allows them to download as certain number of images, so downloading a few more costs them nothing. The cheaper price is what YOU see, not what they pay, depending how many images they download for the subscription period. I haven't read this point made in all the countless Microstock discussions in the forums lately so maybe I have that wrong. If I am right though, then of course a client will try to find the same image elsewhere, effectively for free.
Regardless, Alamy is better known for quality work rather than snapshots (although looking at the huge majority of images available and even many used in Alamy's blogs, I sometimes wonder!) and many clients will choose to come to Alamy first, and if they can't find the image they like in Microstock, they'll buy it from Alamy.