As the hosting business is a low margin business support cost is a very critical area that they want to have as low as possible. In many low-end offerings you actually don’t have any support other than calling high priced hotlines. If you do get support with your offering the hoster still wants the amount of calls be a low as possible. But what happens if a hoster  chooses to aggregate applications or modules of applications for their customers? Who is going to take the support cost and who actually will do the support ? There’s no doubt that this will increase price and complexity of servicing the hosters customers well.