Dan, I have an even better way for them to feel their data is seperate....find a new host.
My theory is simple. I have my own ethics. I don't necessarily have to agree with, condone, or watch/view porn to allow a porn site to buy a server from us. A business in in business to make money. You must follow your own personal ethics, as well as your own business ethics, when running a business.
I find that you can accomodate a lot of people's needs. However, when it comes to beliefs, then the line gets a little harder when determining where it is drawn.
I mean, think about this. I know you said you have nothing against porn, so for this example, we'll pretend you do. Consider that you are looking for hosting, and for example, you find a host that meets your needs perfectly. You do your research on the host and find that their customer service is top notch, according to many happy customers of that host. Now, after contacting the host and asking standard questions, you find that they allow porn sites to reside on their servers, even if they are seperate servers.
Many people who have a dislike for this, will turn down the host, based purely on that aspect. So now, you have to ask yourself where the line is drawn. Does this spill over to other services as well?
Do people who have a strong dislike for porn, enough to turn down a hosting company because of it, also choose not to have electric because a porn studio uses the same electric company? Does it spill over to cellular service, and the person refuses to get a cellphone because some porn moguls have cellphones through many of the cellular providers?
Not to mention, does the line only get drawn at pornographic content? Do Catholic churches choose not to host with a provider who also hosts Baptist websites? The list can literally go on and on.
While these people's beliefs are important, they have to realize that you are providing a service, just like any other industry's service providers. The service you provide to one client is generally none of their concern, so long as it doesn't affect the service you provide to them.
We had one incident where a church wouldn't host with us because we had a casino's website on our servers.
I hate to be the one to tell a church to find a new place to reside, but I really had no choice. I had to prove an ethical point to them. We moved the casino site to a new server, which was then fine with the church. The church then proceeded to set up their website, where they then advertised their weekly bingo, and monthly Las Vegas Night. To me, this seemes like the exact thing they wanted to be seperated from...gambling. So, I pointed this out to them, and said "Another customer does not want to be hosted on the same server as you, so we will need to move you to another server. Is this fine?"
Of course they did not like this, and asked us to simply put the new client on another server. I responded with "Well we need to keep all of the gambling sites in one range, and all of the standard sites in another. Currently your website falls within the gambling genre, because you're advertising gambling events."
This went back and forth for a while, until we simply said, "We have to move your site, or you'll need to find a new host."
Ironically, they're still with us, as they eventually realized that it really wasn't such a big deal, as long as it didn't affect the service we were providing to them.
My experience may sound as though I was being harsh. However, I strongly believe that the only way to educate people about reality is to give them a taste of it.