Gnus and zebras in the Maasai Mara park reserve in Kenya.Ecotourism operations occasionally fail to live up to conservation ideals. It is sometimes overlooked that ecotourism is a highly consumer-centered activity, and that environmental conservation is a means to further economic growth.

Although ecotourism is intended for small groups, even a modest increase in population, however temporary, puts extra pressure on the local environment and necessitates the development of additional infrastructure and amenities. The construction of water treatment plants, sanitation facilities, and lodges come with the exploitation of non-renewable energy sources and the utilization of already limited local resources. The conversion of natural land to such tourist infrastructure is implicated in deforestation and habitat deterioration of butterflies in Mexico and squirrel monkeys in Costa Rica. In other cases, the environment suffers because local communities are unable to meet the infrastructure demands of ecotourism. The lack of adequate sanitation facilities in many East African parks results in the disposal of campsite sewage in rivers, contaminating the wildlife, livestock, and people who draw drinking water from it.

Aside from environmental degradation with tourist infrastructure, population pressures from ecotourism also leaves behind garbage and pollution associated with the Western lifestyle. Although ecotourists claim to be educationally sophisticated and environmentally concerned, they rarely understand the ecological consequences of their visits and how their day-to-day activities append physical impacts on the environment. As one scientist observes, they "rarely acknowledge how the meals they eat, the toilets they flush, the water they drink, and so on, are all part of broader regional economic and ecological systems they are helping to reconfigure with their very activities." Nor do ecotourists recognize the great consumption of non-renewable energy required to arrive at their destination, which is typically more remote than conventional tourism destinations. For instance, an exotic journey to a place 10,000 kilometers away consumes about 700 liters of fuel per person.

Ecotourism activities are, in of itself, issues in environmental impact because they disturb fauna and flora. Ecotourists believe that because they are only taking pictures and leaving footprints, they keep ecotourism sites pristine, but even harmless sounding activities such as a nature hike can be ecologically destructive. In the Annapurna Circuit in Nepal, ecotourists have worn down the marked trails and created alternate routes, contributing to soil impaction, erosion, and plant damage. Where the ecotourism activity involves wildlife viewing, it can scare away animals, disrupt their feeding and nesting sites, or acclimate them to the presence of people. In Kenya, disruption of wildlife observers drive cheetahs off their reserves, increasing the risk of inbreeding and further endangering the species.[