Wait till you get 3 Porygon in a row from 10 km eggs... About getting more 10 km eggs: It is all just luck. Even though I feel that at some stops I get more 10 km eggs, I think that's just perception. It really doesn't matter. It just makes them rarer, same reason you cannot trash 2 km/5 km.
7 km eggs are fine until you got everything from them, then they are pretty much an annoyance. I never open gifts when I got a free egg slot.
Is there any way to trigger getting more 10km eggs rather than 5km or 2k?
Is there any way that you can be more prone to recieve 10km while spinning pokestops rather than other eggs or is it all up to chance?
Just a bit tired of hatching the same boring 2km/5km pokes.
Also why do people like the 7k aloan eggs? why would you want to walk 7k to get a meowth or a diglett? (sorry for my english)
Answers
The thing is that Niantic insists on making us angry with not allowing us to trash 2km and 5km eggs. If I don't want to catch a Pokémon, I can ignore it, and if I catch it and I don't want to keep it, it's ok to trash it.
I mean, I get that this way they make more money out of egg hatchers, but it really is an annoyance within the game features. Oh, and btw Porygon, Chimecho and... Sudowoodo! they still can yield good stardust reward for hatching, so I'm almost ok with them.
Some people claim spinning gyms with a gold badge will give you a better chance at receiving 10km eggs.
Some claim that keeping at least one 10km egg in your inventory increases your chances.
Dunno if any of that actually works. Could just be confirmation bias, and remembering the hits and forgetting the times that they received 5km eggs.
Some initial research showed that certain stops had a higher probability of giving 10k or 2k eggs. Not sure if that's still true or not - the study is hard to do. Convince a statistically significant group of people to spin one stop and only that one stop whenever they have an egg opening. Monitor what they get, collate the data. I suppose you could just have the people spin a small set of stops, and record which egg comes from which stop, but then it would take about a year to get a statistically significant sample from each stop.
Anyway, if you believe that to still be the case, remember the stops where you get 10k eggs and spin them more often when you have an egg opening. If you keep getting 10k from them, focus on them. If not, switch to others.
I’ve noticed something. If you have have the gold gym badge and also have it as your team gym, it seems that you have a good chance of getting a 10k. Of course, right now there is an event going on until tomorrow where you have a increased chance of a 5k and 10k egg. I also noticed that if you spin lure module stops that give you an10k and then spin any other lure modules nearby (quickly, one after the other) you might have an increased chance of getting back to back 10k eggs. However, I’ve noticed that 50% of the time, they tend to be the same Pokemon hatched. But I just want the star dust, so it doesn’t bother me too much. This is just from my observation after hatching 2,092 eggs. Also, the only time 7km eggs tend to be useful is when an event is going on, but they give out crap for star dust and honestly that’s all I really focus on anymore since I’ve hatched every Pokemon I needed. Also, now if you walk 50km a week, you always get a 10k egg, which is pretty nice since I’ve hatched some good Pokemon from them.