Celebrity only 5* on price

Just been on our first Celebrity cruise around the Greek islands. The itinerary and destinations were fantastic and we had a great time.
Unfortunately we were very disappointed with Celebrity having read all reports saying they are 5* and higher class than other cruise line we have used, princess, P&O and Royal Caribbean. maybe we expected too much but we felt that the only thing that was 5* were the prices. when they charge $5.50 for a bottle of water and then add 18% service charge gives you and example.
Maybe cruises are changing but it seems like so many things are excluded and extra charge that you have to be constantly alert and cannot fully relax,
The food was excellent and definitely 5* but service just average, we selected select dinning for the first time as we did not want to eat at 6:15 or 8:45 and being as we had Concierge class cabins that included better seating in the dinning room thought it would be OK, the first two night we got the worst tables in the dinning room next to the kitchen door and serving area, after a few days of constantly requesting to be seated by a window we had tables in slightly better locations, we requested sharing table every night as we wanted to meet other people and only shred on one night, every other night we were just the four of us.
The cabin steward was very poor and we were constantly missing items, we used soap on 3 night to shower with has he had not replenished the shower gel, we gave up asking for it. when we asked it did turn up very promptly but we have never had to ask on other cruises.
I could go on and on but all of these things are minor points and as experienced cruisers we know that this is not 5* service, If celebrity are 5* then Princess must be 6* as we have never had anything other than top class service.
the other real irritation was the dress code on formal nights, we enjoy the spectacle of dressing on formal nights and it all seems very special, not on Celebrity apparently dress code is not enforced !! less than half of the men were wearing tuxedo and their were a lot at dinner in casual dress open shirts with not even a tie on formal night, on lady was in jeans !! if there is going to be a dress code it need to be enforced or we may as well go on one of the cruise lines were they do not have formal evenings.
Luckily all of the crew were very friendly, has I said the destinations were amazing and we had great weather so the niggles did not spoil our cruise just left us thinking next time will not be with celebrity and we may even give up on the formal nights and go for the more modern casual style at least then we would not be expecting 5*