People in Nigeria often visit supermarkets to buy items they need without being sure or are ignorant of the prices of the items beforehand. The advent of the Internet has, however, made it possible to have a prior knowledge of the prices of these items if such supermarkets have websites from which pricing information can be obtained if the customer is computer literate. However, the penetration of the Internet in Nigeria is not as deep as expected and computer literacy in the country is not as pronounced, thus limiting the number of customers that can access the service. But, mobile phone penetration is very high and thus provides an avenue with which to reach a vast majority of Nigerians. In this work, a spoken dialogue system, which is a technology that can be accessed through phones (both feature phones and smartphones) was developed to allow customers to obtain information about the prices of goods they intend to buy in supermarkets through phone calls. A comparison was made of both dual-tone multi-frequency (DTMF) key input and speech modalities for accessing the system. The user satisfaction of the system was measured and the acceptability of the system also determined. The results show that both speech and DTMF are equally satisfying, equally entertaining and equally natural. However, the majority preferred to interact with the system using speech. The majority also supported the supermarkets in Nigeria adopting the technology. The implications of the results obtained is that if introduced, the system will be accepted in Nigeria.