Best practice is to be selfish if you are going to play in the greed game. Companies are no longer loyal to employees like they were back a number of decades, even huge 'career for life' unionized corporations will suddenly have a mass layoff and the executive will put on the 'so sad' act (but not be shy to collect $$$$$$$ bonuses for the 'money saved' when cutting or displacing jobs). Sadly large medium and smaller employers seem to feel it is fair that they can now play that game.
I have a plan B and C, which I keep up to date so that if one day I am fed up or show up to a locked door I can just move on. It is a source of monetary income, not my life, I have changed employers before and the world has not ended. At the moment there is more jobs than wiling workers in the area I live in, so that permitted me some leverage to ask and receive some more money on my paycheque. The sole advantage that my current employer has is that it is only 7 km from my farm, not a huge problem if I had to go further distance if anything should happen to this gig.
Also I do a lot of barter, swap, trade so I do not have to rely solely on my income and savings to live day to day. I lived like a pauper so that I could get to the point where everything I own I actually own, no loans, no rent, no mortgage, no debt. All I owe is the next utility bill. I do not live like royalty, but I have everything I need and a number of wants taken care of as well.