Epson provides Linux drivers for its products through its
Avasys subsidiary. But these are not exactly "Free", since they use binary modules, if that's important to you.
Otherwise, yes, it's going to take time for drivers to be developed. The machines all have to be reverse engineered, which can take days, months, or never. And with increasingly complicated scanner interfaces coming out this can sometimes be almost impossible to do without vendor support. That's a main reason why there aren't many recent Canon drivers, for example. I had a Canon scanner that still isn't usable 3 1/2 years after I got it, because Canon doesn't seem interested in supporting Linux. I switched to an Epson all-in-one and now I can scan and print normally.