Think about car drivers versus pedestrians - car drivers are more likely to yell and curse without reason, because for them the risk of doing so is lower.
If you're being a anonymous jackass, then in the context of an app store this can really hurt an otherwise good app and the developers that are trying to build a good business. Anonymity plays an important role here, because in the real world and on the Internet when you hear or read other people's opinions, you tend to take those opinions with a grain of salt. For example, whenever I post an article on my blog, the second most page for the day is the About page.
An "app store" is different from the Internet at large or from the real world, because an app store is not distributed and because those reviews are used in the search rankings within the app store in a totally dumb way. Problematic is that the reputation of a reviewer or the quality of a review, or the relationship you may have with the reviewer (acquaintance, similar user, etc...) aren't currently taken into account. A review such as "this app sucks" shouldn't have the same weight as a review which explains with a fine level of detail why the app sucks. A review from somebody I know or from somebody that's similar to me shouldn't have the same weight as somebody I don't know.
And yet, that's the status quo right now and both positive and negative reviews represent the truth, determining the success of apps, even though rating is mostly subjective and context dependent.
And I absolutely hate the lack of a feedback cycle. At the very least developers should be allowed to respond to negative reviews with messages such as ... "this was fixed in version XX", or "we are sorry, but the app cannot do that due to platform restrictions", or whatever. I also want to be contacted by the developers, because when posting a negative review I do so because of 2 reasons:
(1) I want to warn others about the dangers ahead, in which case I want to change/delete my review in case whatever I said was not true or was definitely fixed
(2) a negative review is actually better than total indifference and many times when I post the review I do so out of sadness that the app is close to being what I want, but the suckiness is so annoying that I cannot use it, so of course I want to know when that gets fixed
It's worth pointing out that the Internet at large does not suffer from these same problems. People complain that filtering out the noise on the Internet is problematic, but for all the problems associated with its distributed nature and black-SEO, the impression you get about a product when searching on Google tends to be a lot more fair.
How does a third-party, reading your reviews, know that you are telling the truth or not? From the outside, you may sound like an hypercritical annoyance when, in fact, your reviews are completely justified and possibly even understated.
I think this is not significantly different from the dangers of sound bites in politics; too much context is lost when someone searches your name and finds all of these reviews.
An "app store" is different from the Internet at large or from the real world, because an app store is not distributed and because those reviews are used in the search rankings within the app store in a totally dumb way.
That is a valid concern, but I think the anonymity is a flawed solution. Meta-reviewing (Was this review helpful?) and other systems are more adequate and don't have the same drawbacks.