That says more about the shops than it does about maccas, but i agree. I've sampled a few places and very few are anywhere close to what I make at home.
If you follow a few basic principles its not that difficult to make superior coffee at home.
you don't need mega expensive equipment, but there is an element of you get what you pay for, so decent grinders are quite pricey. The grinder is actually more important than the espresso machine.
Once you have the equipment all you need is fresh beans of a flavour that you like. If you drink espresso, beans have a much smaller window of freshness as well. 2 weeks from roast date is getting close to the limit. Once you add milk, its not so critical however most would recommend using beans within 3-4 weeks of roast date.
Do not buy beans from a supermarket. There are plenty of roasters around australia selling very high quality beans.
Once you have your equipment and supplier sorted, then it becomes about technique. This isn't that hard to learn. The 3 main things to learn are grind, dose and tamp. These 3 all go together but should only be adjusted one at a time so you know the effect that change had.
grind = the size of the grounds. Too coarse and it pours too fast. Too fine and it pours too slow. You need to find a sweet spot that achieves approx 30ml in 30sec, give or take.
dose = the amount of ground coffee in the portafilter. Some tampers will have rings around them to act as a guide for consistency. Correct dose should allow about 1mm of space between the top of the puck and the shower screen when the handle is locked in to the espresso machine. An easy way to determine this, is to put a 5c coin on top, lock the handle in, then release and have a look. The coin should not be pushed in but just leave a slight impression in the top of the coffee. Once you have established that, take note of how far in your tamper goes, and don't vary by too much. Its all trial and error.
Tamp = the pressure you push down on the grounds with your tamper. This is probably the one step with the greatest variation in opinion. A friend of mine, who invented Pullman tampers (the best) did numerous tests and found that a pressure of between 5-15kg was ideal. Between those numbers made very little difference. When learning you can tamp on scales to get a feel for it.
It all sounds long winded, but once you get those 3 steps all working in unison to produce that magic 20-30ml in roughly 30sec, then good coffee at home should follow.
If you drink coffee for the taste etc and you regularly buy it, then buying your own equipment can pay for itself in short time. If you drink for the social aspect, then you'll probably end up drinking a lot more coffee
Sorry for long winded post. I do not have expensive equipment as I can't afford it, but I do enjoy the art of making it and trying to teach others as well. My machine is a breville dual boiler (bes920) which has all the features of the best high end machines and is great for domestic duties for those on a tight budget. Its paired with the breville smart grinder, which I can only say 'does the job'. When I win the lottery, that will be getting upgraded, but given I have milk, its not that critical.