We actually stopped charging for our reviews about six months ago, this does limit how many bikes we can cover but we're all about quality over quantity. That's the ideal setup - not charging for reviews helps us to be as objective and unbiased as possible. Since we have a small team it's not like we can cover all the bikes anyways. We've always done our best to be unbiased even when getting paid for reviews... but some people will always be skeptical when we get paid by the manufacturer to produce the review.
Many, many bike companies offer some sort of affiliate program or discount link to us, but we always refuse those. Having a vested interest in the bike selling well would make it really tough to be objective! Even when we did charge for reviews it would be a flat rate paid in advance, so that we wouldn't have a financial incentive to endorse them.
I don't find charging a company for reviewing their product unreasonable. Some older/retired people here may not understand this but you guys are putting a lot of effort in EBR and you should be getting something in return to keep on doing this. That being said, there may be other monetization models which will still keep you free of manufacturers' pressure.
@Court, you and @Angela M. are doing a great job at maintaining these forums. Hopefully EBR will get bigger and you will be rewarded for your efforts as you deserve.