Anchor and some other asian brands sush as Chang are usually a bit cheaper in supermarkets. A 6-pack for 11-12S$ on promo. Tiger is still a premium brand, so that will cost you 15 S$ but as they are all lager the difference in taste in minimal, especially when you start enjoying your beer local stile with ice.
Bar pricing can be whatever, normally I pay for pint about 10-12S$. Some bars ,like North Border, seem to have a continuous monthly promotion 5 dollars for a pint of Stella. 1-for-1 is common happy hour, but some happy hours are just 25% off. Corner coffee shops outside the city sell big tigers (size of two cans) for 6 dollars or less. That is were the local uncles sit down sipping down their CPF savings starting at breakfast hour. Other extremes at Mandarin hotels mezzanine bar you double tiger costs you 30 dollars.
Wine bottles in restaurant start norammly from 40-50S$ range, you might consider that expensive but it is pretty similar to western European prices. In shops though wine is a bit pricey, difficult to find anything below 20S$. Bottles&Bottles often have a promo of basic aussie wine 6 bottles for 100 dollars. Carrefour is another place where you can find cheap promos.
Some wineshops have attached wine bars to them, and in that case they serve the wine for same price (or add 10% Service) if you have it there.
In my home country there is an old saying that alcohol is always worth its price. So people drink either they just pay for it or find a level they can afford. Personnaly I consume wine at home, and beer in bars.
And if you travel enough, bring the hard liquor from the airport.
Any more advice with my favourite pass time needed, and I'm happy to take you to a drinking tour in the east