the old adage about free lunches being rarer than chat threads started by FE applies in equal measure to free web hosting.
If you think about it, why should anyone provide you with a valuable service at no cost whatsoever? The only way a free web host is going to scratch a living is: a) by selling domain names and/or b) by selling advertising space on the site - what you call 'junk' or c) by hoping that you'll pay for additional services, once you're signed up for the free space.
Most free hosts (FreeWebs included) will insist that your site carries at least one banner - often advertising their services - unless you pay for the 'Premium' service. There will also be additional restrictions, and these are usually limitations on the number of files in your space, or on the bandwidth available.