Obviously with government there is corruption and insider baseball and this is the intent of no bid contracts.
Sometimes it's needed. An example would be a winter storm where a town does not have the time to do a open bid process. Which happened.
Or at times is just corruption. Like saying there is only a single provider that can perform all of the requirements. For example, Cheektowaga needs to have water quality sampled but the town puts out some specific requirements like: minority/woman owned, union workforce, located inside of the town itself or have someone at the company with a specific (even if unneeded) certification. In doing so 'they' can pretty much eliminate other companies on purpose and legally. This is the most common way corruption in contracts is done. It's done by both sides as well...it's how you get union yokes on a construction build at 3x the cost and how Halliburton gets DOD contracts....to which they pocket some nice funds as well.
So, while not fair it's legal.