Reasons why companies with union jobs might provide better services due to employees being more personable and reliable:

• Higher wages and better benefits attract people more serious about their work
• Higher wages and better benefits reduce stress in the life of employees, making them more personable on the job
• Unions negotiate employee contracts to limit things like quotas, resulting in lower stress, happier employees

There are probably other reasons too, since I’m just going off the cuff here, but it absolutely makes sense to me that the company with non-union jobs in this industry provides the worst service.