Traveling by air is rife with annoyances, many of which are simply a result of more than 2.5 million human beings in close proximity flying in and out of U.S. airports every day. But in my opinion, some of the problems that travelers endure result from certain entities just not trying hard enough. Here's my list of a handful of air travel frustrations which clearly are never going away.

1. There's a good chance your carry-on will be gate checked.

It's because the number of spots in the overhead luggage compartments doesn't equate with the number of seats. What's unfair about this situation is that many airlines now make people pay to have carry-on luggage larger than what will fit under a seat. How does it make sense to pay extra for your carry-on only to have to end up hanging out in baggage claim to retrieve your stuff? If you peruse travel forums some people claim this wait time can be up to an hour in some airports.

2. It can be tough to get earbuds before the snack and beverage service.

I'm not sure why this is such a big deal, but I have experienced this difficulty a couple of times. On the last flight I took I asked a group of flight attendants chatting amongst themselves for a pair of earbuds and was told they wouldn't be offering them until the snack service started. I admit, it was my fault for forgetting them in the first place, but how is making a person miss out on a half hour of a podcast or movie good for customer satisfaction?

3. Boarding takes forever.

You'd think it makes sense to load passengers in the back of the plane first, but research has determined that back-to-front boarding is the slowest way of getting everybody on board. Likely, this is due to having too many people in one area crawling all over each other to get seated and find an open overhead bin for their carry-on. Alaskan Airlines recently announced a new boarding process in which four groups are boarded after pre-boarding First Class, active military duty and those who need more time. Next to board is Group A, made up of Million Milers and people who have achieved MVP Gold status. Group B is regular MVPs and people who have paid for Premium Class. Folks in the back half of the plane get on next with everybody else in the front getting on last. I suppose rewarding people who've flown a zillion miles makes sense, but still--you'd think someone would figure out a way to speed the process.

4. Bomb sniffing dogs aren't always working the security line.

It's great when they're there because everybody can leave their shoes on and laptops and liquids stashed. TSA employs more than 1,000 teams of dogs and their handlers, but apparently, it's not enough. On the flip side, some people feel that it's not fair to expedite travelers who haven't paid for TSA pre-check.

5. Airlines sell more tickets for a flight than the seats they have available.

How is this practice acceptable, or even ethical for that matter? Everybody remembers the United Airlines passenger who was dragged from an airplane after refusing to give up the seat he had paid for. Well, get this: according to the Los Angeles Times the 12 largest U.S. airlines denied boarding to nearly a half million travelers in 2016, with 41,000 of them removed involuntarily. It's a problem caused by the fact that airlines know a certain percentage of people don't show up for a flight, but with those kinds of numbers their algorithms clearly are not as smart as they should be.

What are your pet peeves related to traveling? I'd love to read your thoughts in the comments.