Kanchipuram is a conservative temple town and alcohol is largely absent from public life here. The few liquor shops that exist are on the outskirts and cater primarily to locals; there are no bars worth the name, and no nightlife in any recognisable sense.
The substitute — and it is a genuine one — is filter coffee. Tamil filter coffee is made by dripping hot water through a metal filter device packed with finely ground dark-roast coffee mixed with chicory, then mixing the concentrate with hot milk and sugar. The result is strong, sweet, and aromatic, served in a small steel tumbler resting in a wide saucer (davara) so you can cool it by pouring back and forth. It bears almost no resemblance to espresso or instant coffee.
Coffee stalls and small tea shops (sometimes called "hotel" in the local usage, confusingly) operate from early morning, clustering near bus stands, temple entrances, and market streets. A tumbler costs almost nothing. For many visitors, learning to drink filter coffee the way it's drunk here — standing at a counter, in conversation or in silence — becomes one of the clearest memories of Tamil Nadu.