Polar Semiconductor interview questions

It's a normal interview process, just started with a phone interview and then an in person one. The pay was below average so I didn't take the offer, and it seemed like people working there knew they were underpaid.

I initially had a virtual interview since I live several hours from the office. I was then invited to have an interview in person. I was interviewed by a panel 5 people. They asked about my work experience and then asked me some logic questions. After the interview (which took an hour), I was given a tour of the clean room (which took over an hour). I had to take the day off of work for this interview and spent money on gas for the 5 hour round-trip drive. I was then told I would hear from the company the week after. I never did. I emailed them to inquire about the position and they told me it had been filled. I spent a lot of time and money for this interview and they did not even tell me they I didn't get the job. It felt very disrespectful.