Bakery and hot snacks vendor Greggs was on a roll over Christmas, with like-for-like (LFL) sales growth of 5.1% in the five weeks to January 7th.Total sales grew by 10.8% for the period. For 2011 as a whole, total sales were up 5.8% from 2010 but the crucial LFL sales figure only rose 1.4%. The firm says it expects 2011 full-year figures to be in line with expectations.Cost inflation in food ingredients began to ease towards the end of the year but rising food and energy costs were a feature of 2011. To counteract this, Greggs says it invested in promotions to retain its "value position" in what it describes as a very competitive market.During 2011 Greggs opened a record 98 new shops and delivered a net increase of 84, after 14 closures. The total number of shops at the end of last year stood at 1,571. The total number of employees has now reached above 20,000 for the first time.The outlook for Greggs is, however, shaped by a "tough trading environment...with consumers' disposable incomes remaining under pressure."The firm says it expects "another year of marginally positive like-for-like sales growth in 2012, while total sales will benefit from the opening of around 90 net new shops".Shares in Greggs were flat in early trading but over the last 12 months the group has gained 15%.bs