I focus on keeping them a member, not giving them every reason to sign up for a single month, download everything on the site, cancel and chargeback. In short, I do not do zips for a reason. Same as we have started eliminating downloads across the board on all pay sites, and adding in throttling.
Will you lose a few members here and there? Maybe. Same as you would on DRM. However, these are members who you probably did not want anyway. Just as you do not want every client, you do not want every member. Not all of them are there for the appreciation of your site. Some are there to smash, grab, and chargeback.
That being said, this is a business. My business is to keep them coming back, and rebilling. Not handing them everything on the site within a month so they can leave via easy of nice convenient downloads. The quality of members you want will not need those zips, or to be able to download a whole site in a single billing period (i.e. throttling their downloads).
